Pulmonary Function Tests
by Editorial Staff and Contributors
Pulmonary function tests (PFTs) are a group of tests to assess breathing. They can show how well your lungs are working. PFTs may measure:
Reasons for Test
PFTs may be used to help diagnose lung conditions or diseases, such as:
These tests may also be done to:
There are no major complications linked to this procedure.
What to Expect
Prior to Test
Description of Test
Most tests will require you to breathe into a mouthpiece. The mouthpiece may be attached to a simple handheld device or be part of a larger machine. Examples of devices are:
You may be asked to breathe in and out in different patterns and speeds. You will rest between tests.
Tell the technician right away if you have breathing problems, pain, or dizziness during the test.
Other steps that may be needed include:
You may be asked to breathe in small amount of carbon monoxide for 1 minute. It will be followed to see how much gets into your blood. This will suggest how well oxygen is getting into your blood.
Rest until you feel able to leave. You may be given treatment if testing has caused wheezing, coughing, and/or problems breathing.
How Long Will It Take?
Will It Hurt?
The test does not hurt. You may feel some symptoms during or right after testing.
Your doctor will compare the results of your tests with normal values. Your age, gender, and height, or previous test results will be considered as well. Your doctor will discuss the results with you. If needed, further testing or treatment plans will be made.
Call Your Doctor
After the test, call your doctor if any of the following occurs:
American Lung Association
Family Doctor—American Academy of Family Physicians
Beyerle J. Spirometry for the primary care provider. JAAPA. 2014 Dec;27(12):28-34.
Parker M. Interpreting spirometry: the basics. Otolaryngol Clin North Am. 2014 Feb;47(1):39-53.
Pulmonary function tests. EBSCO DynaMed Plus website. Available at: http://www.dynamed... . Updated May 27, 2016. Accessed August 29, 2017.
Pulmonary function studies. EBSCO Nursing Reference Center website. Available at:
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Updated January 1, 2015. Accessed September 19, 2017.
Last reviewed September 2018 by EBSCO Medical Review Board Michael Woods, MD, FAAP
Last Updated: 3/30/2018
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